This invention relates generally to decorative wood articles and more particularly methods of fabricating decorative wood articles using powder coatings to reduce volatile organic emissions.
Powder coatings are being used to coat more articles in industrial applications because powder coatings are more environmentally friendly than liquid coatings. Powder coatings are virtually free of volatile organic compounds (VOC) that are present in most liquid coatings. Consequently, the solvent or VOC emissions problems associated with liquid coatings are eliminated by powder coatings which enables industrial business to meet federal and local air pollution regulations.
Despite their many advantages, powder coatings are typically not used to coat heat sensitive substrates, such as wood and plastic, because of the high temperatures generally needed to cure powder coatings.
It would be desirable to provide a method of fabricating a decorative wood article utilizing powder coatings. Further it would be desirable to provide a method of fabricating a decorative wood article that included a heat sensitive decorative overlay on the surface of the wood utilizing powder coatings.
In an exemplary embodiment of the present invention, a method of fabricating a decorative wood article utilizes radiation curable powder coatings to reduce VOC emissions. The method includes applying a decorative overlay onto a surface of a wood article, such as natural wood, particleboard, fiberboard, or medium density fiberboard, and applying a powder coating onto the outer surface of the overlay. The wood article can be heated prior to the application of the powder coating to enhance the electrostatic attraction of the powder coating to the wood article. After application of the powder coating onto the surface of the decorative overlay, the powder coating is melted by heating the coating. Heating of the coating is accomplished, for example, with an infrared (IR) heater, a convection heater, or a combination of convection heat and IR. The temperature used is sufficient to melt and flow the powder coating while not degrading the wood substrate and/or the decorative overlay. The powder coating is then exposed to radiation energy to cure the powder coating and form a film on the top surface of the decorative overlay.
The above described method provides for the fabrication of a decorative wood article that includes a decorative overlay applied to the surface and that utilizes a radiation curable powder coating. The radiation curable powder coating produces virtually no VOC emissions during the application and curing process. The powder coating application and curing steps do not degrade the wood substrate nor the decorative overlay.